Screening,Identification of Antagonistic Bacteria against Rhizoctonia solani and Preparation of Its Active Ingredient by Fermentation

[Objective]The aim was to study the fermentation conditions of antagonistic bacteria active ingredient against Rhizoctonia solani.[Method]Some antagonistic bacteria against R. solani were screened through point inoculating contrary to R. solani on agar petri plates and shaking flask fermentation; the obtained strain was identified through morphological identification and 16 S RNA sequencing to construct phylogenetic tree; and fermentation conditions of active ingredient of the obtained strain against R. solani were studied through single factor experiment. [Result]Seventeen strains of bacteria antagonist R. solani were obtained,and strain Lys-67 was obtained finally; strain Lys-67 was identified as Bacillus subtilis. Also,150 μl fermentation broth of strain Lys-67 resulted in 36 mm of inhibition zone against R. solani,determining by method of drilling hole with Oxford cup on agar plate,while strain Lys-67 was cultured in wheat bran 5. 0%,at 35 ℃,rotation speed200 r /min for three days. [Conclusion]The results lay basis for further study and application of strain Lys-67.